1. Field of the Invention
This invention relates to a tuner control system and more specifically to an improvement in an automatic tuner control system in which when a station broadcasts a program in several waves (i.e. frequencies or wavelengths), the device automatically selects one of those waves which is at a higher level than a predetermined reference level, thus being in a well receivable condition.
2. Description of the Prior Art
In a conventional automatic tuner, there has been proposed a so-called "frequency diversity system" for switching waves by detecting an electric field intensity or a noise level to thereby compare them with respective reference levels.
However, such conventional system has various problems because it carries out the wave switching with a simple judgement of the result of the comparison with the above described reference level. Particularly, when it is adopted in a short-wave broadcasting with a large fading, the wave switching frequently takes place, thus to frequently interrupt the reproduced sound every time the wave switching occurs.
Conventionally, there has also been proposed another system in which there are provided a plurality of receivers in order to carry out the wave switching by comparing the outputs of these receivers therebetween.
However, the above system has drawbacks regarding its production cost and space, considering that such system should generally be mounted in a radio set for a common use which is generally small in size.